Asymptotically flat (1,m,n) superstrata: a farewell to AdS

TL;DR

This paper extends the family of superstrata geometries to include flat asymptotics, moving beyond the AdS regime, which is a step towards more realistic models of black hole microstates in our universe.

Contribution

It introduces flat asymptotics into the (1,m,n) superstrata family, highlighting the complexities and potential for future research beyond the decoupling regime.

Findings

Holomorphicity is obscured in flat space coupling.

Consistent truncation is broken in flat asymptotics.

Progress towards phenomenologically relevant microstate geometries.

Abstract

Superstrata microstate geometries furnish some of the most successful laboratories, to date, for probing black hole microstructure in a geometric setting. This paper extends the (1,m,n) family of superstrata, to allow for flat asymptotics. Previous constructions utilized the decoupling regime, where the geometry is asymptotically AdS3xS3. Brief comments are made on the additional complexity introduced by the flat space coupling, how this obscures holomorphicity and breaks the consistent truncation to which the decoupled solutions belong. Holomorphicity and consistent truncation were key simplifications assisting previous studies of the (1,m,n) superstrata, undertaken in the decoupling regime. Further, these results open a window for future projects to determine how previous analysis on the decoupled geometries extend or are modified once flat space asymptotics are imposed. Since our universe is almost flat on cosmological scales, this represents progress towards more phenomenologically relevant microstate geometries. This work can be considered a continuation of that in arxiv.org/abs/1711.10474 where some single mode superstrata were also coupled to flat space.